diff --git a/scripts/runner.py b/scripts/runner.py
index d4610114827801f53707665572ad96f0c8054a4a..f758563a8c9bf35d4a5f6e81dda63e1089892a89 100755
--- a/scripts/runner.py
+++ b/scripts/runner.py
@@ -44,7 +44,7 @@ def main():
     interaction = "CC" if args["--CC"] else "NC"
     flavour = "electron" if args["--electron"] else (
         "muon" if args["--muon"] else "tau")
-    target = (args["--target-a"], args["--target-z"])
+    target = (args["--target-z"], args["--target-a"])
 
     jc = generate_neutrino_jobcard(events,
                                    interaction,